Transport Imaging in the One Dimensional Limit
Abstract
Transport imaging is a SEM-based technique used to directly image the motion and recombination of charge in luminescent semiconductors, allowing for the extraction of transport parameters critical to device operation. In this thesis, transport imaging for 1-D structures was initiated with work on sample preparation, modeling and initial characterization. One dimensional structures are being integrated into forefront electronics due to their inherent advantages in size, packing density and power consumption. In this work the one dimensional equation for steady state minority carrier recombination distribution solved for the Gaussian source is derived and results from numerical simulations are presented. The diameter of the SEM beam is determined experimentally allowing for accurate simulation parameters. Intensity and drift measurements on four batches of top-down wire structure samples, fabricated on a AlGaAs/GaAs/AlGaAs double heterostructure using a FIB, are presented. Significant decreases in luminescence in FIB exposed regions are reported. Spatial luminescence from single bottom-up GaN and ZnO nanowires deposited by metal initiated metal-organic CVD on Au and SiO2 substrates is imaged. CL spectra for GaN and ZnO, with peak intensities at 3.27 and 3.29 eV, are characterized. Finally, several suggestions for further research are offered including transport imaging on contacted bottom-up nanowires and a potential application of transport imaging to FIB damage characterization.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 2006
- Accession Number
- ADA457725
Entities
People
- Stephen D. Winchell
Organizations
- Naval Postgraduate School